FW V06.XX/HAFM SW V08.02.00 HP StorageWorks SAN High Availability Planning Guide (AA-RS2DD-TE, July 2004)
Table Of Contents
- SAN HA Planning Guide
- Contents
- About this Guide
- Introduction to HP Fibre Channel Products
- Product Management
- Planning Considerations for Fibre Channel Topologies
- Fibre Channel Topologies
- Planning for Point-to-Point Connectivity
- Characteristics of Arbitrated Loop Operation
- Planning for Private Arbitrated Loop Connectivity
- Planning for Fabric-Attached Loop Connectivity
- Planning for Multi-Switch Fabric Support
- Fabric Topologies
- Planning a Fibre Channel Fabric Topology
- Fabric Topology Design Considerations
- FICON Cascading
- Physical Planning Considerations
- Port Connectivity and Fiber-Optic Cabling
- HAFM Appliance, LAN, and Remote Access Support
- Inband Management Access (Optional)
- Security Provisions
- Optional Features
- Configuration Planning Tasks
- Task 1: Prepare a Site Plan
- Task 2: Plan Fibre Channel Cable Routing
- Task 3: Consider Interoperability with Fabric Elements and End Devices
- Task 4: Plan Console Management Support
- Task 5: Plan Ethernet Access
- Task 6: Plan Network Addresses
- Task 7: Plan SNMP Support (Optional)
- Task 8: Plan E-Mail Notification (Optional)
- Task 9: Establish Product and HAFM Appliance Security Measures
- Task 10: Plan Phone Connections
- Task 11: Diagram the Planned Configuration
- Task 12: Assign Port Names and Nicknames
- Task 13: Complete the Planning Worksheet
- Task 14: Plan AC Power
- Task 15: Plan a Multi-Switch Fabric (Optional)
- Task 16: Plan Zone Sets for Multiple Products (Optional)
- Index
Planning Considerations for Fibre Channel Topologies
109SAN High Availability Planning Guide
Fabric Topology Design Considerations
This section discusses additional fabric topology design considerations, including:
■ Large Fabric Design Implications
■ FCP and FICON in a Single Fabric
■ Multiple Data Transmission Speeds in a Single Fabric
■ Fibre Channel Distance Extension
Large Fabric Design Implications
Businesses are experiencing an unprecedented growth of information and the
requirement to maintain that information online. To meet these requirements,
Fibre Channel SANs provide the infrastructure to connect thousands of servers to
hundreds of storage devices. To provide enterprise-class SAN performance and
scalability, large fabric designs are required.
When multiple directors or switches are connected, ISL (E_Port) communication
must be established between fabric elements and the fabric must be initialized.
During fabric initialization, the fabric elements:
■ Establish the operating mode for connected E_Port pairs and exchange link
parameters (E_Port names, timeout values, class-specific information, and
flow control parameters).
■ Exchange fabric parameters, select a principal switch, and assign domain IDs
to all switches.
■ Employ a routing protocol to establish the shortest path through the fabric and
program route tables for each fabric element.
■ Exchange the active zone set to ensure uniform zoning is enforced between all
fabric elements.
However, fabric initialization is not a serial process. The process executes
concurrently across all ISLs in the fabric, causing a massive flood of Class F
traffic that must be processed to the embedded port of each fabric element within
a specified (fabric-wide) error detect time-out value (E_D_TOV). If the fabric
consists of a large number of elements (and therefore ISLs), Class F traffic may
not be processed within the E_D_TOV, resulting in error recovery operations,
time-outs, segmented links, or fabric failure.